A method for treating cellulosic fibers to improve paper, board and tissue quality; the method involves splitting fibers from feed pulp into an original portion containing original fibers and a refineable portion containing original fibers. The refinable portion is refined to create a refined portion containing refined fibers. Varying amounts of the original unrefined fibers and refined fibers are blended together to form a recombined slurry that is processed by a paper machine into an optimized paper product. A master control system and fiber measurement system are integrated with the overall system to regulate all processing.